Spark plug wrench



Nov. 6, 1934. J. H. MELVIN SPARK PLUG WRENCH Filed July 1, 1933 John H. NcZYig;

Patented Nov. 6, 1934 umreo STATES P ATE SPARK PLUG WRENCH John H. Melvin, Rochester, N. Y.

Application July 1, 1933, Serial-N0. 6783676 2Claims. (01. 81-55) The invention relates to a spark plug wrench. The object of the present invention is to improve the construction of spark plug wrenches and to provide a simple, practical and eificient I spark plug Wrench of great strength and durability designed particularly for'use by motorists on the-road as well as other places and adapted to be readily applied to a spark plug for removing the same from a motor and capable after a spark plug has been removed from a motor of being readily operated to separate or take apart the spark plug for removing, replacing or repairingthecore without danger of accidentally cracking, breaking or otherwise injuring the porcelain of the spark plug.

A- further object of the invention is to provide a relatively light spark plug wrench in which the fastening device for holding the parts in assembled relation will-be relieved of the strain incident to the operation of the wrench so that there will be no liability of the fastening devices being injured orbroken when it is necessary to exert considerable force in removing a spark plug or separating the parts thereof.v

Another object of the invention is to provide a spark plug wrench adapted to be operated with greaterfacility than those heretofore constructed and capable of eliminating all tendoncy to cant or twist when force is applied to the members of the wrench.

A further object of the invention is" toequip the'spark'plug wrench with adapters for varying the size of the hexagonal opening which receives the body portion of thespark plug which adapter will enable the Wrench to fit different sizes of spark plugs so'that it will not be necessary'to purchase spark plugs of a particular size to fit the wrench.

It isalso an object of the invention to provide an adapter for extending the opening or socket which'engages the bodyportion of a spark plug so that thewrench when equipped with an adapter will fit over and properly engage most any spark plug for removing the same from a motor. Y

With these and other objects in view, the invention consists in the construction and novel combination and. arrangement of parts hereinafter fully. described; illustrated in the accompanying drawingandpoi'nted out in the claims hereto appended, it being understood that various changes in the form, proportion and minor details of -construction, within the scope of the claims, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

Figure 1' is a side'elevation. of aspark plug wrench constructed in accordance with this invention.

Fig. 2 is a longitudinal sectional view of the same, showing the Wrench applied to a spark plug the latter being illustrated in dotted lines.

Fig. 3 is a plan view of one of the wrench members showing the inner face thereof.

.Fig. 4 is a similar View of the other wrench member.

Fig. 5 is a plan view of the cylindrical bearing member. I

Fig. 6 is a similar View of the retaining plate.

Fig. 7 is a perspective view of the adapter.

In the accompanying drawing in which is illustrated thepreferred embodiment of the invention the spark plug wrench comprises in its construction lower and upper wrench members 1 and 2, a cylindrical bearing member 3 and a retaining plate 4. The lower Wrench member 1 consists of a circular head 5 and a straight handle 6 and the upper wrench member consists of a circular head '7 and a handle 8 which is angularly bent intermediate of its ends at spaced-points to provide an inclined intermediate portion 9 which offsets the grip of the handle 8 from the grip of the handle 6 so that both handles may be readily gripped by the operator when one is located directly over the other whereby it is unnecessary to first place the wrench on a spark plug 10 with the handles in an angularly related position. The Wrench can be operated to separate the parts of the spark plug.

The bearing member? consists of a ring having a cylindrical opening with lower and upper portions 11 and 12 of different diameters forming a horizontal shoulder or seat 13 for the retaining plate 4.. The lower wrench member is provided with a relatively large hexagonal opening- 14 to receive and permit the wrench member to engage the lower body portion 15 of the spark plug.

The head 5 of the lower wrench member is provided at its inner or upper face with a cylindrical boss or flange 16 extending entirely around the hexagonal opening 14 and forming short extension of the walls thereof and having a' cylindrical peripheral face to fit within the reduced portion 11 of the opening of the bearing member 3. The bearing member consists of a ring and the cylindrical boss 16 snugly fits within the portion 11 of the opening of the ring and is retained therein by the plate 4 which is circular and of a diameter to fit snugly within the portion 12 of the opening of the bearing member. The retaining plate 4 which has a hexagonal opening 17 corresponding to the opening 14 of the wrench member 1 is secured to the latter by screws 18 or other suitable fastening means. These fastenings 18 are located withinthe assembledparts of the wrench. The

retaining plate retains the cylindrical boss 16 of the wrench member 1 concealed within the cylindrical bearing member and forms a swivel connection between the cylindrical bearing member and the wrench member so that there is no strain on the screws 18 when pressure is applied to the wrench members for turning or partially rotating the same. This is due to the fact that the cylindrical boss 16 of the lower wrench member fits snugly within or is embraced by the cylindrical bearing portion 11 of the bearing member and is permitted to turn freely while being prevented from tilting or canting.

The head 7 of the upper wrench member 2 is provided with a relatively small hexagonal opening 19 to fit or engage the hexagonal portion 20 of the section 21 of the spark plug 10 and the said head '7 is provided at its inner face with a cylindrical boss 22 forming a short extension of the walls of the hexagonal opening 19 of the head 7 and being of a diameter to snugly fit within the enlarged portion 12 of the bearing member 3. The wrench member 2 is secured to the cylindrical bearing member by screws 23 or other suitable fastening devices which pierce the head 7 and engage threaded openings or holes in the bearing member 3. As the cylindrical boss 22 fits snugly within the enlarged upper portion 12 of the opening of the bearing member there is no liability of the upper wrench member twisting or canting. As the bearing member 3 turns freely with relation to the lower wrench member 1 there will be no strain on the fastening devices 23 when pressure is applied to the wrench.

Owing to the angular bends and the offsetting of the grip of the handle 8 from the grip of the handle 6 the thickness of the heads of the wrench members and the bearing member may be reduced to a minimum as there will be ample space between the grips or handles to enable both to be simultaneously grasped by the operator when one is located directly in parallelism with the other. This will enable a much lighter wrench to be constructed than would be the case were it necessary to increase the width or thickness of the bearing member 3 to provide such space.

Also the fitting of the cylindrical bosses of the heads of the wrench members within the cylindrical opening of the bearing member will prevent any tendency of the wrench members to tilt or cant in the operation of the wrench and the grip portions of the wrench members may be spaced any desired distance apart for convenience of operation without liability of causing the wrench to tilt or cant.

In order to enable the wrench to engage spark plugs of difference diameters and to fit over almost any spark plug for removing'the same from a motor the spark plug wrench is equipped with a tubular adapter 24 of hexagonal form having an exterior 25 of a size to fit the relatively large hexagonal opening 14 of the wrench member 2 and provided with a hexagonal opening 26 of a diameter less than the hexagonal opening 14 to fit a spark plug having a body smaller than the spark plug 10. In practice th wrench will be equipped with a plurality of tubular hexagonal adapters each having an exterior fitting the p ng of the wrench member 2 while the hexagonal openings of the adapters will vary in size to fit spark plugs having bodies of different sizes. Only one of the adapters is illustrated in the drawing but as the only difference will be a variation in the size of the opening it is believed that further illustration of this feature is unnecessary. The adapter not only provides an opening of a difierent size from the opening 14 but also extends the walls thereof so as to readily fit over and engage most any spark plug for removing the same from a motor.

These adapters will enable spark plugs of different sizes to be purchased and used on motors without necessitating purchasing wrenches of different sizes to suit the different spark plugs and when it is necessary to use an adapter to fit a particular set of spark plugs the adapter may be left in the wrench in position for instant use when required.

What is claimed is:

1. A spark plug wrench comprising two wrench members having polygonal openings of different sizes to fit the wrench receiving portions of a spark plug, said wrench members being provided with short integral cylindrical bosses of substantially the same length and entirely surrounding the respective polygonal openings and forming extensions directed inwardly toward each other transversely of the wrench members, a cylindrical bearing member having a central opening therein which loosely embraces and conceals both of said bosses and which spaces the wrench members apart, and a retaining ring concealed within and overlying a portion of said bearing member and interposed between said bosses in engagement with the opposed faces of the latter and secured to one of the bosses, whereby the latter boss is retained within said bearing member and the respective wrench members thereby swiveled in the bearing member, and means for securing the other wrench member to the bearing member for retaining the respective I bosses within the bearing member.

2. A spark plug wrench comprising wrench members having openings therein of difi'erent sizes to fit wrench receiving portions of a spark plug, said wrench members having cylindrical bosses on their inner faces surrounding said openings and forming bosses projecting inwardly toward each other, the bosses being relatively short and of substantially the same length, a relatively shallow rotatable bearing member interposed between the wrench members and engaging the same to space them slightly apart and having a central opening with portions of different diameters forming an interior shoulder, a thin retaining plate of cylindrical form fitted upon said shoulder within the larger diameter of the opening of said bearing member and concealed within the latter between said bosses, means connecting said plate to one of said bosses to retain the one of the wrench members in cooperative swiveled relation with said bearing member, said securing means being wholly confined and concealed within the bearing member whereby, incident to the rotatable movement of the bearing member and the embracing relation thereof with said bosses the wrench members are prevented from canting with relation to each other and the said fastening means is relieved of strain incident to pressure on the wrench in use and the fastening means thereby prevented from canting, and means for securing the other wrench member to said bearing member for retaining its boss within the bearing member.

JOHN H. MELVIN. 

